1. Field of the Invention
The invention lies in the field of heat measurement, in particular, the continuous measurement of the quantity of heat exchanged in a load equipment by a heat-conveying liquid flowing therethrough by an integrating flow calorimeter.
2. Description of the Prior Art
When a heat-conveying liquid is used as a heating or cooling medium and is supplied to individual dwellings in a housing area or district, and an integrating flow calorimeter is used to continuously sense and indicate the total quantity of heat supplied to, or removed from, the load equipment by the heat-conveying liquid, it is very desirable that the electric power required for running the calorimeter be supplied by a battery incorporated in the device. However, prior to the present inventIon, known integrating flow calorimeters required comparatively large quantities of electrical power for their operation, and thus could not be continuously operated for long periods of time by a battery which could be integrally mounted within the meter.
Also, in prior known integrating flow calorimeters having a rotating vane type of liquid flowmeter, the speed ratio of a geared transmission system was adjusted in order to calibrate the flowmeter and correct for any inherent measurement error. This involved changing the gears in the transmitting system to obtain the correct combination of gears and thus the correct speed ratio, a procedure which was both difficult and time-consuming.
Also, prior to the present invention, copper resistance sensing elements had generally been used as the sensing elements to measure the supply and exhaust temperatures of the heat-conveying liquid. However, these copper resistance sensing elements were too large in size to be installed in a pipe of a size which would otherwise be normal and adequate for many load equipments, for example, load equipment for heating individual dwelling houses. These copper resistance sensing elements were not only difficult to install, but considerably increased the flow resistance of the liquid path.